Non-coplanar magnetic order and topological magnons in tripod kagome antiferromagnet Yb<sub>3</sub>Mg<sub>2</sub>Sb<sub>3</sub>O<sub>14</sub>

ORAL

Abstract

Kagome antiferromagnet is one of the most studied models for geometrical frustration which is expected to be a topological magnon insulator in the presence of Dzyaloshinskii–Moriya interactions. The recent discovered tripod kagome materials provide us a platform to explore such ideas with strongly spin-orbit coupled rare earth ions. Using elastic neutron scattering measurements, we show that one of the tripod kagome compounds, Yb3Mg2Sb3O14, orders into a strongly non-coplanar magnetic ground state below 0.88 K which calls for large antisymmetric exchanges. Inelastic neutron scattering experiment on polycrystalline samples reveals both dispersive and flat magnon bands which can be fitted by an anisotropic exchange Hamiltonian derived from a symmetry analysis. Along with numerical calculations, our results unveil Yb3Mg2Sb3O14 as a candidate to host topological non-trivial magnon bands.

*The work at Georgia Tech was sponsored by the Department of Energy under DE-SC-0018660.

Presenters

  • Zhiling Dun

    • Georgia Inst of Tech
    • School of Physics, Georgia Institute of Technology
    • Physics, Georgia Institute of Technology
    • Georgia Institute of Technology

Authors

  • Zhiling Dun

    • Georgia Inst of Tech
    • School of Physics, Georgia Institute of Technology
    • Physics, Georgia Institute of Technology
    • Georgia Institute of Technology

  • Owen Benton

    • Riken center for Emergent Matter Science
    • Max Planck Institute for the Physics of Complex Systems

  • Xiaojian Bai

    • Georgia Inst of Tech
    • School of Physics, Georgia Institute of Technology
    • Georgia Institute of Technology

  • Nicholas Butch

    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • National Institute of Standards and Technology
    • Center of Neutron Research, National Institute of Standards and Technology
    • Center for Neutron Research, National Institute of Standards and Technology
    • NIST Center for Neutron Research
    • NIST center for neutron research
    • NIST
    • NIST Center for Neutron Research, National Institute of Standards and Technology,
    • University of Maryland, College Park & NIST
    • National Institute of Standards and Technology Center for Neutron Research

  • Haidong Zhou

    • University of Tennessee
    • Department of Physics and Astronomy, University of Tennessee, Knoxville
    • University of Knoxville, Tennessee
    • Department of Physics & Astronomy, University of Tennessee
    • University of Tennesse, Knoxville
    • Physics and anstronomy, University of Tennessee
    • Department of Physics, University of Tennessee
    • Physics, University of Tennessee, Knoxville
    • University of Tennessee, Knoxville

  • Martin Mourigal

    • Georgia Inst of Tech
    • School of Physics, Georgia Institute of Technology
    • Physics, Georgia Institute of Technology
    • Georgia Institute of Technology